Sounds like your acupuncturist is sensitive, can sense emotion in others. Do you think he mentioned your depression as a way of acknowledging how you might be feeling? Do you feel it was a simple acknowledgement (a polite and basically caring acknowledgement), a heartfelt acknowledgement of support and compassion or one where he's offering you the freedom to openly express yourself (an invitation)?
Not sure what type of acupuncturist he is. Is he a physio type, where he's solely treating physical issues or is he a general energy based acupuncturist who is more so into releasing any energy/chi related blocks so as to restore flow? Perhaps a bit of both. Reason I ask relates to me wondering whether he's raising the depression based on him genuinely caring while wondering whether he can treat you for it in some way. Perhaps he's trying to gain a sense of whether you might be open to that. What do you feel?
Being a mind/body/spirit sort of gal, certain energy practices fascinate me, acupuncture included. The idea that emotion (aka energy in motion or blocked energy not in motion in come cases) is something we can feel is interesting. While I can appreciate modern medicine and how it specifically identifies a number of energetic pathways that run through and connect the nervous system, vascular system, endocrine system, muscular system etc, in traditional medicine the pathways are 'channels'. How energy's behaving and running through the channels or not running through them freely can be revealing, even on a psychological level. A good acupuncturist will 'pinpoint' the flows and the blocks and can work to release the energetic blocks. I've actually heard some people describe the release of an emotional block through acupuncture to have the same feel as a significant mind altering revelation. Both have a bit of a physical rush to them that comes with a sense of sudden release. In energy healing, such as with acupuncture, if the practitioner pinpoints the right spot there can even be a sudden overwhelming release of tears and emotion. While blocks can involve an integration of many emotions, a sudden disintegration can trigger great emotion to be released all at once (free flowing energy) which can have a positive impact on the mind and body.
Could he actually be the person to make a significant difference to you after all these years? Can't help but wonder. Maybe you could sound him out.
As my heart goes out to you I wish you freedom from your pain.